Wearable article having elastic belt

ABSTRACT

Disclosed is a wearable article comprising a main body and a ring-like elastic belt comprising a front belt and a back belt, where the entirety of the length of the belt side edge of the front belt may be seamed with a certain length of the belt side edge of the back belt to define a seam length LS. The front and back belts may be each divided into 4 zones, where the tensile stress of the front proximal tummy zone may be higher than the tensile stress of any of the front waist zone, the front distal tummy zone, or the front leg zone, and the tensile stress of the back distal tummy zone may be higher than any of the tensile stress of the back waist zone, the back proximal tummy zone, or the back leg zone.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation, under 35 USC 120, of Application No.CN2014/085239, filed on Aug. 27, 2014, Application No. CN2015/072192,filed on Feb. 4, 2015, Application No. CN2016/073256, filed on Feb. 3,2016, and Application No. CN2016/074564, filed on Feb. 25, 2016, whichare herein incorporated by reference in their entirety.

BACKGROUND OF THE INVENTION

Infants and other incontinent individuals wear wearable articles such asdiapers to receive and contain urine and other body exudates. Pull-onwearable articles, or pant-type wearable articles, are those which aredonned by inserting the wearer's legs into the leg openings and slidingthe article up into position about the lower torso. Pant-type absorbentarticles have become popular for use on children who are able to walkand often who are toilet training, as well as for younger children whobecome more active in movement such that application of taped-typeabsorbent articles tends to be more difficult.

Many pant-type wearable articles use elastic elements secured in anelastically contractible condition in the waist and/or leg openings.Typically, in order to insure full elastic fit about the leg and thewaist such as is provided with durable undergarments, the leg openingsand waist opening are encircled at least in part with elasticizedelements positioned along the periphery of the respective opening.

Pant-type wearable articles having a main body to cover the crotchregion of the wearer and a separate elastic belt defining the waistopening and leg opening are known in the art, such as described in PCTPublication WO 2006/17718A. Such pant-type wearable articles may bereferred to as belt-type pants. On the other hand, certain pant-typewearable articles are configured such that the outer cover of thewearable body completely covers the entirety of the garment-facingsurface of the article. Such pant-type wearable articles may be referredto as uni-body pants. Belt-type pants, compared to uni-body pants, maybe advantageous in having better breathability by having less layers ofmaterial in certain areas of the articles, and in that they may bemanufactured economically. Whether the uni-body type or belt-type, thereis a desire to provide pant-type wearable articles in more or less agarment like appearance, including providing the side seam as straightas possible. Meanwhile, there is a desire to provide pant-type wearablearticles to better fit the human body, particularly to a lower torso ofa child of less than 36 months of age. Compared to that of an adult, theyoung child has a relatively bigger front waist. To conform to such bigfront waist area, there may be provided a pant extending to the higherportion of the torso. However, considering the advantages of thebelt-type pants described above, such extending of the pant may not beof interest from a breathability and cost point of view.

Based on the foregoing, there is a need for a pant-type wearable articlehaving balanced performance such as fit, coverage of buttock area,comfort during wear, prevention of sagging, and prevention of leakage.There is further a need for providing such a wearable article in aneconomical manner.

SUMMARY OF THE INVENTION

The present intention is directed to a wearable article continuous in alongitudinal direction and a transverse direction, comprising a mainbody and a ring-like elastic belt comprising a front belt and a backbelt, the center of the front belt is joined to a front waist panel ofthe main body, the center of the back belt is joined to a back waistpanel of the main body, the front and back belt each having a left sidepanel and a right side panel where the main body does not overlap, andthe transverse edges of the front belt and the back belt are joined by aseam to form a waist opening and two leg openings,

wherein each of the front belt and back belt are formed by an innersheet, an outer sheet, and a plurality of elastic bodies sandwichedtherebetween and running in the transverse direction substantiallyparallel to each other,

wherein each front belt and back belt have transversely continuousproximal and distal edges, the proximal edge being located closer thanthe distal edge relative to the longitudinal center of the article, eachfront belt and back belt having side edges,

wherein the entirety of the length of the belt side edge of the frontbelt is seamed with a certain length of the belt side edge of the backbelt to define a seam length LS;

the front and back belts each divided into 4 zones extending in thetransverse direction and defined by its location from the distal edge tothe proximal edge relative to the percentage of the seam length LSwherein; 0-25% is the waist zone, 25-50% is the distal tummy zone,50-85% is the proximal tummy zone, and 85-100% is the leg zone;

wherein the tensile stress of the front proximal tummy zone is higherthan the tensile stress of any of the front waist zone, the front distaltummy zone, or the front leg zone, and

the tensile stress of the back distal tummy zone is higher than any ofthe tensile stress of the back waist zone, the back proximal tummy zone,or the back leg zone.

BRIEF DESCRIPTION OF THE DRAWINGS

While the specification concludes with claims particularly pointing outand distinctly claiming the subject matter which is regarded as formingthe present invention, it is believed that the invention will be betterunderstood from the following description which is taken in conjunctionwith the accompanying drawings and which like designations are used todesignate substantially identical elements, and in which:

FIG. 1 is a perspective view of one embodiment of a wearable article ofthe present invention.

FIG. 2 is a schematic plan view of one embodiment of a wearable articleof the present invention with the seams unjoined and removed, and in aflat uncontracted condition showing the garment facing surface.

FIG. 3 is a schematic side plan view of one embodiment of a wearablearticle of the present invention in a flat uncontracted conditionshowing the garment facing surface.

FIG. 4 is a side view of one embodiment of a wearable article of thepresent invention worn on a mannequin.

FIG. 5 is a side view of a wearable article of the prior art worn on amannequin.

FIG. 6 is a schematic view of an example of a hanger-type sample holdingfixture according to the “Whole Article Force Measurement”.

FIG. 7 is a side view of one embodiment of a wearable article of thepresent invention worn on a stretch board according to the “Belt SeamShape Measurement”.

FIG. 8 is a schematic plan view of one embodiment of a wearable articleof the prior art with the seams unjoined and removed, and in a flatuncontracted condition showing the garment facing surface.

FIG. 9 is a schematic side plan view of one embodiment of a wearablearticle of the prior art in a flat uncontracted condition showing thegarment facing surface.

DEFINITIONS

As used herein, the following terms shall have the meaning specifiedthereafter:

“Wearable article” refers to articles of wear which may be in the formof pants, taped diapers, incontinent briefs, feminine hygiene garments,and the like. The “wearable article” may be so configured to also absorband contain various exudates such as urine, feces, and menses dischargedfrom the body. The “wearable article” may serve as an outer coveradaptable to be joined with a separable disposable absorbent insert forproviding absorbent and containment function, such as those disclosed inPCT publication WO 2011/087503A.

“Pant” refers to disposable absorbent articles having a pre-formed waistand leg openings. A pant may be donned by inserting a wearer's legs intothe leg openings and sliding the pant into position about the wearer'slower torso. Pants are also commonly referred to as “closed diapers”,“prefastened diapers”, “pull-on diapers”, “training pants” and“diaper-pants.”

“Longitudinal” refers to a direction running substantially perpendicularfrom a waist edge to an opposing waist edge of the article and generallyparallel to the maximum linear dimension of the article.

“Transverse” refers to a direction perpendicular to the longitudinaldirection.

“Body-facing” and “garment-facing” refer respectively to the relativelocation of an element or a surface of an element or group of elements.“Body-facing” implies the element or surface is nearer to the wearerduring wear than some other element or surface. “Garment-facing” impliesthe element or surface is more remote from the wearer during wear thansome other element or surface (i.e., element or surface is proximate tothe wearer's garments that may be worn over the disposable absorbentarticle).

“Disposed” refers to an element being located in a particular place orposition.

“Joined” refers to configurations whereby an element is directly securedto another element by affixing the element directly to the other elementand to configurations whereby an element is indirectly secured toanother element by affixing the element to intermediate member(s) whichin turn are affixed to the other element.

“Extendibility” and “extensible” mean that the width or length of thecomponent in a relaxed state can be extended or increased.

“Elasticated” and “elasticized” mean that a component comprises at leasta portion made of elastic material.

“Elongatable material,” “extensible material,” or “stretchable material”are used interchangeably and refer to a material that, upon applicationof a biasing force, can stretch to an elongated length of at least about110% of its relaxed, original length (i.e. can stretch to 10 percentmore than its original length), without rupture or breakage, and uponrelease of the applied force, shows little recovery, less than about 20%of its elongation without complete rupture or breakage as measured byEDANA method 20.2-89. In the event such an elongatable material recoversat least 40% of its elongation upon release of the applied force, theelongatable material will be considered to be “elastic” or“elastomeric.” For example, an elastic material that has an initiallength of 100 mm can extend at least to 150 mm, and upon removal of theforce retracts to a length of at least 130 mm (i.e., exhibiting a 40%recovery). In the event the material recovers less than 40% of itselongation upon release of the applied force, the elongatable materialwill be considered to be “substantially non-elastic” or “substantiallynon-elastomeric”. For example, an elongatable material that has aninitial length of 100 mm can extend at least to 150 mm, and upon removalof the force retracts to a length of at least 145 mm (i.e., exhibiting a10% recovery).

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective view of an embodiment of the wearable article 20of the present invention and FIG. 2 is a schematic plan view of the samearticle with the seams unjoined and in its flat uncontracted conditionshowing the garment-facing surface. The wearable article 20 has alongitudinal centerline L1 which also serves as the longitudinal axis,and a transverse centerline T1 which also serves as the transverse axis.The wearable article 20 has a skin-facing surface, a garment-facingsurface, a front region 26, a back region 28, a crotch region 30, andseams 32 which join the front region 26 and the back region 28 to formtwo leg openings and a waist opening. The wearable article 20 comprisesa main body 38 to cover the crotch region of the wearer, a front belt 84and a back belt 86 (hereinafter may be referred to as “front and backbelt”), the front and back belts 84, 86 forming a ring-like elastic belt40 (hereinafter may be referred to as “waist belt”) extendingtransversely defining the waist opening. The front and back belts 84, 86and the main body 38 jointly define the leg openings.

The main body 38 may contain an absorbent core 62 for absorbing andcontaining body exudates disposed on the main body 38. In the embodimentshown in FIG. 2, the main body 38 has a generally rectangular shape,left and right longitudinally extending side edges 48 (hereinafter maybe referred to as “side edge”) and front and back transversely extendingend edges 50 (hereinafter may be referred to as “end edge”). The mainbody 38 also has a front waist panel 52 positioned in the front region26 of the wearable article 20, a back waist panel 54 positioned in theback region 28, and a crotch panel 56 between the front and back waistpanels 52, 54 in the crotch region 30. The center of the front belt 84is joined to a front waist panel 52 of the main body 38, the center ofthe back belt 86 is joined to a back waist panel 54 of the main body 38,the front and back belt 84, 86 each having a left side panel and a rightside panel 82 where the main body 38 does not overlap.

Referring to FIGS. 1 and 2, the ring-like belt 40 formed by the frontbelt 84 and back belt 86 acts to dynamically create fitment forces andto distribute the forces dynamically generated during wear. Herein, theterm “proximal” is used to indicate the position of a “proximal” portionbeing closer relative to the longitudinal center of the article, alsocloser relative to the crotch panel 56 of the main body 38 than theposition of a “distal” portion. Therefore, the proximal edge 90 islocated closer than the distal edge 88 relative to the crotch panel 56of the main body 38. The front and back belts 84, 86 may be joined witheach other only at the side edges 89 at the seams 32 to form a wearablearticle having a waist opening and two leg openings. Each leg openingmay be provided with elasticity around the perimeter of the leg openingby the combination of elasticity from the front belt 84, the back belt86, and any from the main body 38. The front leg opening region 120 isdisposed adjacent the leg opening along the proximal edge 90 of the leftand right side panels 82 of the front belt 84.

The front and back belts 84, 86 are discontinuous with one another inthe crotch region 30. In such embodiment, there is no material thatcovers the entirety of either the wearer-facing surface orgarment-facing surface of the article. The front central panel 80 maypartly overlap with the front waist panel 52 of the main body 38. Theback central panel 80 may partly overlap with the back waist panel 54 ofthe main body 38. However, the central panels 80 may not extend into thecrotch panel 56 of the main body 38 and not be disposed in the crotchpanel 56. In the embodiment shown in FIG. 2, the central panels 80partly overlap with and are joined to the front waist panel 52 and theback waist panel 54, respectively.

Referring to FIG. 2, the front belt 84 and back belt 86 may eachcomprise an inner sheet 94, an outer sheet 92, (hereinafter alsocollectively “belt sheets”) and a plurality of elastic bodies 96sandwiched therebetween and running in the transverse directionsubstantially parallel to each other, and configured to impartelasticity per each zone according to the relationship described below.(The inner sheet 94 is not shown.) Such an article may be economicallymade.

In one embodiment, the effective transverse width LW of the back belt 86in the uncontracted condition may be the same as the transverse width ofthe front belt 84 of the same condition. By “effective transversewidth”, what is meant is the width available for forming thewearer-facing surface of the article. In one embodiment, each of theproximal edges 90 and the distal edges 88 of the front belt 84 and theback belt 86 may be substantially parallel, as in FIG. 2.

In one embodiment, the longitudinal length LB of the back belt 86between the back distal edge 88 and the back proximal edge 90 along itsentire width LW of the back belt 86 may be approximately the same as thelongitudinal length LF of the front belt 84 between the front distaledge 88 and the front proximal edge 90. In such embodiment, the seams 32close the front and back belt 84, 86 side edges 89 of the same lengthfor forming the article. Such an article may be economically made.

In one embodiment, the back belt 86 may have a greater longitudinallength LB between the back distal edge 88 and the back proximal edge 90along its entire width LW of the back belt 86 in the transversedirection than the longitudinal length LF of the front belt 84 betweenthe front distal edge 88 and the front proximal edge 90 (FIGS. 1-3). Insuch embodiment, when the wearable article is assembled to form thewaist opening and the leg openings, the wearable article 20 is foldedalong the transverse centerline T1 such that the front distal edge 88 isaligned with the back distal edge 88. The front side edge 89 is alsoaligned with a portion of the back side edge 89. Then the front belt 84and the back belt 86 are joined at the front and back side edges 89 atthe seams 32. The front and back proximal edges 90, however, may not bealigned to one another. The back proximal edge 90 may be disposedlongitudinally closer than the front proximal edge 90 relative to thetransverse center line T1 such that the proximal portion of the backside panel 82 extends toward the crotch panel 56 of the main body 38beyond the front proximal edge 90. The side edge of the proximal portionof the back side panel 82 may not be joined to anywhere and free fromattachment. Thus, the proximal portion of the back side panel 82provides a buttock cover 95 as in FIG. 1.

Whether or not the longitudinal length LB of the back belt 86 and thelongitudinal length LF of the front belt 84 are the same, the entiretyof the longitudinal length LF of the belt side edge 89 of the front belt84 is seamed with the belt side edge 89 of the back belt 86 to define aseam length LS, as in FIG. 3. When the front belt 84 has straight distaledges 88 and proximal edges 90 that are substantially parallel of eachother, then the longitudinal length LF of the front belt 84 is equal tothe seam length LS.

In one embodiment, the outer sheet 92 of the front or back belt 84, 86towards the distal edge 88 may be longer than the size of the innersheet 94 in the longitudinal direction, and an end flap of the outersheet 92 may be folded over the distal end of the inner sheet 94 at thewaist opening. The front and back belts 84, 86 may be provided in lowcaliper non-woven material for sake of breathability and softness of thebelt 40.

The tensile stress (N/m) of the front and back elastic belts 84, 86,respectively, may be profiled in order to provide the benefits of thepresent invention. The tensile stress may be measured, for example, bythe Belt Zone Tensile Stress Measurement described herein below. Whenthe elasticity of the front and back elastic belts 84, 86 are providedby a plurality of elastic bodies 96 running in the transverse direction,the tensile stress may be adjusted by one or more of the followingmethods; 1) elongation rate of the elastic body 96; 2) density (dtex) ofthe elastic body 96; 3) longitudinal interval of multiple elastic bodies96; and 4) effective length of elasticity of the elastic body 96 in thetransverse direction. By elongation, “0% elongation” is meant theoriginal length of the elastic body. When a portion of an elastic bodyis removed of its elasticity, the remainder of the intact elastic bodycapable of imparting elasticity is defined as the “effective length ofelasticity of an elastic body”. The elastic bodies 96 disposed on thefront and/or back belt 84, 86 may be treated such that certain of thearea overlapping the front and/or back waist panels 52, 54 of the mainbody 38 are removed of elasticity. Removal of elasticity from at least aportion of the area overlapping the front and/or back waist panel 52, 54of at least one elastic body may be advantageous when the main body 38comprises an absorbent core 62, in that elasticity in the front and/orback area may cause bunching of the absorbent core 62 and interfere withclose fit of the main body 38 to the wearer. In one embodiment, at leasta portion of, or at least 10% of, or at least 20% of, or at least 30%of, the elasticity of; at least one of, or at least half of, or at leasttwo thirds of, or all of, the elastic bodies are removed in the regionoverlapping with the front and back waist panels 52, 54 or the absorbentcore 62 of the main body 38.

Referring to FIG. 3, the front and back belts 84, 86 are each dividedinto 4 zones extending in the transverse direction and defined of itsposition from the distal edge 88 to the proximal edge 90 relative to thepercentage of the seam length LS. The entirety of the length of the beltside edge 89 of the front belt 84 is seamed with a certain length of thebelt side edge 89 of the back belt 86 to define a seam length LS. Whenseam length LS is considered 0% at the distal edge 88 and 100% at theproximal edge 90 of the front belt 84, the zones are defined as such:0-25% is the waist zone 102, 25-50% is the distal tummy zone 104, 50-85%is the proximal tummy zone 106, and 85-100% is the leg zone 108. Whenthere is an elastic body disposed at 25% from the distal edge 88, suchelastic body is considered to be included in the waist zone 102. Whenthere is an elastic body disposed at 50% from the distal edge 88, or 85%from the distal edge 88, such elastic body is considered to be includedin the proximal tummy zone 106. For embodiments where the back belt 86has a greater longitudinal length LB than the longitudinal length LF ofthe front belt 84, the remaining length of “LB minus LS” of the backbelt 86 is not counted in the 4 zones described above.

In the article of the present invention, the tensile stress of the frontproximal tummy zone 106 may be provided higher than the tensile stressof any of the front waist zone 102, the front distal tummy zone 104, orthe front leg zone 108. The tensile stress of the front proximal tummyzone 106 may be higher than the tensile stress of any other zone, eitherin the front or the back. The tensile stress of the front proximal tummyzone 106 may be no less than 200% of the tensile stress of the frontdistal tummy zone 104. In one embodiment, the tensile stress of thefront distal tummy zone 104 may be lower than, or no more than 70% of,the tensile stress of the back distal tummy zone 104. In one embodiment,the tensile stress of the front proximal tummy zone 106 may be no lessthan 150% of the tensile stress of the back proximal tummy zone 106. Thetensile stress of the back distal tummy zone 104 may be provided higherthan any of the tensile stress of the back waist zone 102, the backproximal tummy zone 106, or the back leg zone 108. When comparing the 4zones each of the front belt and the back belt, the tensile stress maybe provided greatest in the order of: the front proximal tummy zone 106,followed by the back distal tummy zone 104.

Without being bound by theory, such profiling of the tensile stress perzone is believed to provide the article of the present invention with ashaped elastic belt 40 that conforms well to a human body, particularlyto a lower torso of a child of less than 36 months of age, and thereforeprovide good fit and comfort to the wearer, without compromise ofsagging prevention or leakage prevention. Namely, the front proximaltummy zone 106 is subject to high tensile stress such that the articlemay be anchored against the wearer's trochanter, while leaving more areafor the back proximal tummy zone 106 to accommodate the wearer'sbuttock. As long as the article is anchored securely at the trochanter,the leg zone 108 adjacent the leg opening may be provided withsignificantly less tensile stress compared to the proximal tummy zone106. Thus, the soft fit at the front leg opening region 120 facilitatesleg movement. Further, by providing a higher tensile stress to the backdistal tummy zone 104 compared to the front distal tummy zone 104, thewearer's front waist area is accommodated.

As a result of the profiling as described above, the article of thepresent invention may take an S-curve side seam 32 observed by the sidewhen worn by the wearer, as shown as in FIG. 4. In that the front belt84 is pulled toward the front side due to the highest tensile stress inthe article of the front proximal tummy zone 106, the remainder of theside seam 32 may be curved accordingly. When the waist belt 40 of thepresent invention is measured against the Belt Seam Shape Measurementmethod described hereinbelow, the d value may be no less than +10 mm, orno less than +15 mm, or no less than +20 mm. Such d value is indicativeof the article conforming to the relatively greater front waist area andbuttock area of the wearer, while providing good anchoring at the frontproximal tummy zone 106. The curved side seam 32 and positive d value isobserved no matter how the stretch board 180 is inserted in the sample,so long as a certain amount of time is allowed for the sample to reachequilibrium. Such behavior of the waist belt 40 of the present inventionis in contrast with many belt-type wearable articles available in themarket as shown in FIG. 5, wherein the side seam 32 takes a relativelystraight line, or a line slightly slanted toward the back. For thearticle of FIG. 5, the d value according to the Belt Seam ShapeMeasurement herein may be negative. When the waist belt 40 of thearticle of the present invention is stretched to 70% of its fullstretch, the seam 32 may be curved to the extent it has a width alongthe transverse axis of no less than +10 mm, or no less than +15 mm, orno less than +20 mm.

The tensile stress of the front leg zone 108 may be provided lower thanthe tensile stress of any of the front waist zone 102, the front distaltummy zone 104, or the front proximal tummy zone 106. The tensile stressof the back leg zone 108 may also be provided lower than the tensilestress of any of the back waist zone 102, the back distal tummy zone104, or the back proximal tummy zone 106. In one embodiment of thepresent invention, the tensile stress of the front leg zone 108 may befrom 80% to 200% of the tensile stress of the back leg zone 108. Suchrelationship of tensile stress may be advantageous for providing softfit at the front leg opening region 120 and facilitate leg movement. Inone embodiment, the tensile stress of the front waist zone 102 may befrom 80% to 120% of the tensile stress of the back waist zone 102.

The profiling and arrangement of elastic bodies 96 of FIG. 3 may providethe article of the present invention to take an uneven forcedistribution between the front belt 84 and the back belt 86. The elasticbodies may be configured such that the total of the tensile stressprovided by the front waist zone 102, the front distal tummy zone 104,the front proximal tummy zone 106, and the front leg zone 108; may begreater than the total of the tensile stress provided by the back waistzone 102, the back distal tummy zone 104, the back proximal tummy zone106, and the back leg zone 108. Such uneven force distribution betweenthe front belt 84 and the back belt 86 may be advantageous for anchoringthe article on the front side of the body, or for sagging prevention orleakage prevention.

The article of the present invention may have a plurality of elasticbodies disposed on each of the zones for providing the tensile stress.The elastic bodies disposed on the front proximal tummy zone 106 mayhave a density of no less than 540 dtex. The elastic bodies on the frontproximal tummy zone 106 may be disposed at an elongation of at least250%. In one embodiment, from 6 to 18 elastic bodies may be disposed onthe front proximal tummy zone 106.

In one embodiment, at least some, or at least 3, of the elastic bodiesin the front waist zone 102 and those in the back waist zone 102 may beso configured to more or less match locations at the side seam 32. Inone embodiment, at least some, or at least 3 of the elastic bodies inthe front leg zone 108 and those in the back leg zone 108 may be soconfigured to more or less match locations at the side seam 32. In oneembodiment, the front and back waist zones 102 may be disposed of 3 or 4elastic strands closest to the waist opening and matching at the sideseam 32, such that the gathers created by the elastic strands provide awaist band appearance 126 as shown in FIG. 4. In one embodiment, thefront and back leg zones 108 may be disposed of 3 or 4 elastic strandsclosest to the front leg opening region 120 and matching at the sideseam 32, such that the gathers created by the elastic strands provide aleg band appearance 128 as shown in FIG. 4. The waist and leg bandappearances 126, 128, may connote good fit or leakage prevention to thewearer or caregiver.

Still referring to FIG. 4, in one embodiment, the waist zone 102comprises one interval between elastic bodies of 10-20 mm. Suchrelatively large interval may provide gathers suitable as a finger hook130 in which the wearer or caregiver may insert fingers for ease ofpulling up the article 20. The gathers for providing a waist bandappearance 126 described above may also function as the ergonomicallyfavorable finger hook 130. In one embodiment, 2-3 elastic bodies locatedclosest to the waist opening are disposed with an interval of 2-4 mm tocreate an array of elastic bodies and matched at the side seam 32, andthe interval adjacent such array of elastic bodies may provide a fingerhook 130.

The elastic profiling described herein may be utilized for economicallymaking an article of no less than 420 mm, or no less than 450 mm, or noless than 500 mm in the longitudinal axis by using a total of no morethan 60, or no more than 46 elastic bodies for the elastic belt 40 perarticle. The article of the present invention may have an entirelongitudinal length of the article of from 350 mm to 600 mm, aneffective transverse belt width (LW) of from 315 mm to 500 mm, a backbelt longitudinal length (LB) of from 100 mm to 180 mm, a front beltlongitudinal length (LF) of from 80 mm to 160 mm, a main bodylongitudinal length of from 310 mm to 560 mm, and a main body transversewidth of from 150 mm to 210 mm. The article of the present invention mayhave a distance between the distal edge of the front belt to thelongitudinal edge of the main body of from 0 mm to 70 mm, and a distancebetween the distal edge of the back belt to the longitudinal edge of themain body of from 0 mm to 90 mm, and such distances on the front andback belt may be the same or different. The longitudinal length of themain body may be from 70% to 100% of the entire longitudinal length ofthe article. When the main body comprises an absorbent core 62, the coremay have a longitudinal length of from 270 mm to 500 mm, a maximumtransverse width of the core of from 90 mm to 125 mm, and a distancebetween the longitudinal edge of the core to the longitudinal edge ofthe main body of from 10 mm to 40 mm. The longitudinal length of thecore may be from 60% to 95% of the entire longitudinal length of thearticle, or from 66% to 97% of the main body.

The article of the present invention may have a Waist CircumferenceForce provided by the elastic bodies 96 disposed on the waist belt 40 ofno more than 10N, or no more than 8N, according to the Whole ArticleForce Measurement as described herein below. The Whole Article ForceMeasurement is for quantifying the force provided by the article 20 whenstretched along the waist circumference, simulating initial stretchexperience of the article 20 in the transverse direction when the userinserts hands in the article and expands the article. Namely, more orless the total tensile force provided by the elastic bodies 96 disposedin the transverse direction is measured. While there may be otherelastic bodies disposed on the article, for example along thelongitudinal side edges of the main body, the impact of such otherelastic bodies are known to be small, when the user stretches thearticle in the transverse direction. The Whole Article Force Measurementis obtained by extending, or loading, the article in the transversedirection until a force of 19.6N is attained, wherein the force at thepoint where the belt 40 article reaches 70% of the maximum stretch isobtained. The force expected to be perceived by the user for expandingthe article may be controlled, such that the user may experience asatisfying expansion of the belt 40 without excess effort.

In one embodiment, the elongation of the elastic bodies disposed on thefront and back of the same zone are substantially matched. When acertain length of the elastic body is removed of its elasticity, theeffective length of elasticity of such elastic body is considered. Bymatching the elongation rate of the elastic bodies disposed on the frontand back of the same zone, and having the front and back belt 84, 86have the same width LW, the article 20 may be manufactured such that inthe unstretched, contracted condition, the article 20 can be flattened.The aforementioned shaping effect of the article 20 conforming to thewearer's body shape is exerted only when the article 20 is in thestretched, wearable condition. Such flattening capability is found formany commercially available pant-type wearable articles, and providesmany benefits for providing the article economically. The capability ofbeing flattened accommodates assembling, transferring, and packaging ofthe article 20.

The obtained wearable article of the present invention may provide fit,coverage of buttock area, comfort during wear, prevention of sagging,and prevention of leakage. The obtained wearable article of the presentinvention may be made in an economical manner.

Whole Article Force Measurement

Force is measured using an Electronic Tensile Tester with a computerinterface such as the MTS Criterion C42 running TestWorks 4 Software(available from MTS SYSTEMS (CHINA) CO., LTD) or equivalent instrument.A load cell is selected so that force results for the samples testedwill be between 10 and 90% of capacity of the load cell used. Theinstrument is calibrated according to the manufacturer's instructions.All testing is performed in a room maintained at 23±2° C. and 50±5%relative humidity.

The tensile tester is fitted with hanger-type sample holding fixtures300 as shown in FIG. 6. Each fixture comprises a rigid linearrubber-coated horizontal bar section 302 to prevent sample slippageduring testing. The outer bar diameter (including the rubber coating) ofthe horizontal bar sections is 10.0 mm. The central axes of thehorizontal bar sections 302 are configured to remain parallel and in thesame vertical plane throughout the test procedure. The gaugecircumference is determined by the following equation:

Gauge Circumference=2×(H+D+πD/2)

where H is the vertical gap between the horizontal bar sections 302, andD is the outer diameter of the bar.

The instrument is set up to go through the following steps:

Crosshead Speed 254.0 mm/min Final Load Point 19.61 N Hold Time 0 Numberof Cycles 1 Data Acquisition Rate 50 Hz

A sample article 20 is inserted onto the upper horizontal bar section302 so that the bar passes through the waist opening and one leg openingof the article. The crosshead is raised until the specimen hangs abovethe lower bar and does not touch lower bar 302. The load cell is taredand the crosshead is lowered to enable the lower bar 302 to be insertedthrough the waist opening and other leg opening without stretching thearticle. The article is adjusted so that the longitudinal centerline L1of the article is in a horizontal plane halfway between the upper andlower bars 302. The center of the side portion in contact with the bar302 is situated on the same vertical axis as the instrument load cell.The crosshead is raised slowly while the article is held in place byhand as necessary until the force is between 0.05 and 0.1N, while takingcare not to add any unnecessary force. The gauge circumference at thispoint is the Initial Gauge Circumference. The test is initiated and thecrosshead moves up at 254 mm/min until a force of 19.6N is attained,then the crosshead immediately returns to the initial gaugecircumference at the same speed. The maximum circumference at 19.6N andthe force at 70% stretch circumference during the extension segment ofthe test are recorded.

Circumference(mm)=2×(H+D+πD/2)

The maximum circumference at 19.6N is defined as the Full StretchCircumference (mm). The 70% stretch circumference is defined as the fullstretch circumference ×0.7. The Waist Circumference Force is defined asthe force at 70% stretch circumference during the load (extension)segment of the test.

Five samples are analyzed and their average Initial Gauge Circumference,average Full Stretch Circumference and average Waist Circumference Forceare calculated and reported to the nearest 1 mm, 1 mm and 0.01 N,respectively.

Belt Zone Tensile Stress Measurement

The tensile stress (N/m) is calculated by tensile force (N) divided bythe specimen width (m). Force may be measured using an ElectronicTensile Tester with a computer interface such as the MTS Criterion C42running TestWorks 4 Software (available from MTS SYSTEMS (CHINA) CO.,LTD) or equivalent instrument. A load cell is chosen so that forceresults for the samples tested will be between 10 and 90% of capacity ofthe load cell. The instrument is calibrated according to themanufacturer's instructions. All testing is performed in a roommaintained at 23±2° C. and 50±5% relative humidity. The instrument isequipped with single line contact grips at least as wide as the testspecimen.

To obtain test specimens, the sample article is cut open along the sideseams 32, and the front and rear elastic belt sections 40 are removedfrom the main body 38 by separating the bonding between the waist beltand main body. Cold Spray may be used, paying attention not to makewrinkles in the belt sections. Care is taken not to spray on any beltelastic body 96. The obtained elastic belts 40 are severed into zones102, 104, 106, 108 according to the present invention with care not tocut any elastic body 96. Samples are pre-conditioned at 23° C.±2 C.° and50%±5% relative humidity for two hours prior to testing.

The instrument is set up to go through the following steps. InitialGauge Length is calculated from the Initial Gauge Circumference which isdetermined during the Whole Article Force Test using separate identicalarticles, as described above. Initial Gauge Length=0.5×Initial GaugeCircumference. The final gauge length is calculated from the FullStretch Circumference which is determined during the Whole Article ForceTest, as described above.

Crosshead Speed 254.0 mm/min Data Acquisition Rate 50 Hz Final GaugeLength 0.5 × Full Stretch Circumference Hold Time 0 Number of Cycles 1

One end of the specimen is clamped into the upper clamp and the load istared. The other end of the specimen is clamped into the lower clamp.Approximately 5 mm of each end of the specimen is behind the contactline of the grip. The test is started and the specimen is extended tothe final gauge length at a crosshead speed of 254 mm/min, thenimmediately returned to the original gauge length at the same speed. Thespecimen is extended in the article transverse direction during thetest. The unload force at 70% of the Final Gauge Length during theunload segments of the test is recorded.

Five articles are analyzed and the unload forces are recorded for eachof the front and back zones 102, 104, 106, 108. The average tensileforce (N) is calculated to the nearest 0.01 N for each zone includingthe front and back specimens for that zone. The tensile stress for eachzone is calculated by the average tensile force (N) divided by theaverage longitudinal length (m) and reported to the nearest 0.1 N/m.

Belt Seam Shape Measurement

A belt specimen from a pant type absorbent article 20 and a board forsupporting the sample according to the size of the sample (hereinafter“stretch board”) are prepared.

The belt specimen is prepared by removing the waist belt 40 from themain body 38 of the article by separating the bonding between the waistbelt and main body. Cold Spray may be used, paying attention not to makewrinkles in the belt sections. Care is taken not to spray on any beltelastic body 96. The seam length LS (see FIG. 3) of the sample ismeasured to within ±1 mm with the belt laid flat and no tension applied.

The Full Stretch Circumference is determined during the Whole ArticleForce Test using different articles of the same batch, as describedabove. The Full Stretch Width is defined as 50% of the Full StretchCircumference.

The stretch board is 180 made of polymethyl methacrylate, polycarbonate,or similar rigid material and has a dimension as such:

Thickness 8.5 mm ± 5 mm Length Between [the seam length (LS) + 40 mm] to[the seam length (LS) + 100 mm] Width 70% of the Full Stretch Width ofthe sample specimen - board thickness

For example, if the belt side seam length LS is 130 mm, the stretchboard length should be 170-230 mm. If the Full Stretch Width of thespecimen is 355 mm, and the board thickness is 8.5 mm, the board widthshould be 240 mm.

The stretch board 180 is inserted in the specimen while stretching thespecimen as little as possible to insert the board, and in a manner suchthat the entire length of the seams 32 are placed on the front and backplanes (and not on the sides) of the stretch board 180, such as shown inFIG. 7. The specimen is adjusted on the stretch board 180 so that thedistal edge 88 (i.e. at the waist opening) of each seam 32 on one sideand the other of the stretch board 180, as well as the proximal edge(i.e. at the leg opening) of each seam 32 on one side and the other ofthe stretch board 180 are aligned to within ±5 mm, respectively, of thesame longitudinal axis.

The specimen with the stretch board 180 inserted is then stood for 1 minto reach equilibrium in an environment at 25±2° C. and 50±10% RH. Thelinear end-to-end side seam length (rather than the contour length) inthis stretched condition (LSS) is measured. The positions of the seam 32in the transverse direction at points 70% of LSS away from the waistopening (70% point) and at 25% of LSS away from the waist opening (25%point) in the longitudinal direction are measured, and the difference“d” (unit: mm) is obtained (see FIG. 7). The value d is positive whenthe 70% point is located closer to the front longitudinal centerline ofthe belt compared to the 25% point. The value d is negative when the 25%point is located closer to the front longitudinal centerline of the beltcompared to the 70% point. The d value is obtained for both seams 32 oneither side of the stretch board 180. The “d” values are measured forfive identical articles and the average d value (average of 10 values)is reported to the nearest 1 mm.

EXAMPLES Example 1

A wearable article of the present invention having an elastic profilingaccording to FIGS. 2, 3, and Table 1 below having an effective beltwidth LW of 355 mm and a seam length LS of 130 mm.

Comparative Example 1

A wearable article of the prior art having an elastic profilingaccording to FIGS. 8, 9 and Table 1 below having an effective belt widthLW of 355 mm and a seam length LS of 130 mm.

TABLE 1 dtex/elongation %/ number of elastic bodies Comparative Example1 Example 1 Front waist zone 540 dtex/170%/4 940 dtex/210%/3 Frontdistal 540 dtex/170%/2 940 dtex/210%/3 tummy zone 540 dtex/275%/ 680dtex/275%/ 2 with tummy cut 1 with tummy cut Front proximal 540dtex/275%/ 680 dtex/275%/ 2 with tummy cut 5 with tummy cut tummy zone940 dtex/275%/ 6 with tummy cut Front leg zone 540 dtex/275%/ 680dtex/275%/ 2 with tummy cut 2 with tummy cut Back waist zone 540dtex/170%/4 940 dtex/210%/3 Back distal 940 dtex/170%/4 1100 dtex/170%/3tummy zone Back proximal 540 dtex/275%/ 680 dtex/275%/ tummy zone 6 withtummy cut 4 with tummy cut Back leg zone 540 dtex/275%/ 680 dtex/275%/ 2with tummy cut 3 with tummy cut

Elastic bodies indicated as “tummy cut” are removed of elasticity at thecentral area of the central panels 80 overlapping with the main body 38,and have 66% effective length of elasticity.

The Waist Circumference Force and tensile stress for each zone weremeasured according to the Whole Article Force Measurement and Belt ZoneTensile Stress Force Measurement methods herein, respectively, forExample 1 and Comparative Example 1. The value d was measured accordingto the Belt Seam Shape Measurement method herein, for Example 1 andComparative Example 1. Results are found in Table 2.

TABLE 2 Example 1 Comparative Example 1 Waist Circumference Force (N)6.12 5.99 Tensile Stress (N/m) Front waist zone 27.4 36.3 Front distaltummy zone 27.4 29.8 Front proximal tummy zone 107.7 25.7 Front leg zone19.5 22.1 Back waist zone 28.6 32.0 Back distal tummy zone 49.5 39.4Back proximal tummy zone 32.5 20.4 Back leg zone 20.5 23.1 Value d (mm)+25 negative

For Example 1, the total of the tensile stress provided by the frontwaist zone, the front distal tummy zone, the front proximal tummy zone,and the front leg zone; is greater than the total of the tensile stressprovided by the back waist zone, the back distal tummy zone, the backproximal tummy zone, and the back leg zone.

For Example 1, the tensile stress of the front proximal tummy zone ishighest among any other zone, and is more than 200% of the tensilestress of the front distal tummy zone 104, and is more than 150% of thetensile stress of the back proximal zone. For Example 1, the tensilestress of the back distal tummy zone is higher than any of the tensilestress of the back waist zone, the back proximal tummy zone, or the backleg zone, and when comparing the 4 zones each of the front belt and theback belt, the tensile stress is greatest in the order of: the frontproximal tummy zone, followed by the back distal tummy zone. Also forExample 1, the tensile stress of the front waist zone 102 was between80-120% of the tensile stress of the back waist zone 102, and thetensile stress of the front leg zone 108 was between 80-200% of thetensile forces stress of the back leg zone 108. Also for Example 1, thetensile stress of the front leg zone is lower than the tensile stress ofany of the front waist zone, the front distal tummy zone, or the frontproximal tummy zone, and the tensile stress of the back leg zone islower than the tensile stress of any of the back waist zone, the backdistal tummy zone, or the back proximal tummy zone.

For Comparative Example 1, the tensile stress of the front proximaltummy zone is lower than the tensile stress of the front distal tummyzone 104, and is less than 150% of the tensile stress of the backproximal zone.

Example 1 provided profiling of tensile stress per zone withoutsignificant increase of total tensile force of the belt compared toComparative Example 1.

Compared to Comparative Example 1, Example 1 provides improvement in oneor more of: fit, coverage of buttock area, comfort during wear,prevention of sagging, prevention of leakage, fit around waist, softnessof inside of the belt, prevention of red marking, overall softness,looking soft, and perceived overall quality.

Consumer Acceptance

Example 1 and Comparative Example 1 including an identical absorbentcore were subjected to a consumer test for application on 50 panelistsand 51 panelists, respectively. The panelists were caregivers ofJapanese Size 4 (L-size) wearers of age 0-36 months, and at about thesame boy/girl ratio. The caregivers of the panelists were given enoughproducts to use either product for 5 days, and then answer aquestionnaire including the following questions, and asked to rate theperformance in 5 scales from “Very Poor” to “Excellent”, wherein 100represents “Excellent”, 75 represents “Good”, 50 represent “Fair”, 25represent “Poor” and 0 represents “Very Poor”. The ratings were averagedand statistically analyzed. Test results are shown below in Table 3.

TABLE 3 Comparative Question Example 1 Example 1 Overall Rating  77* 69Overall Softness  86* 71 Belt Softness 79 70 Overall Fit Of The PantWhen The 72 64 Diaper Is Full Overall Quality Of The Product  80* 71Preventing Skin Problems Such As 70 62 Rash/Redness/Would Cause YouConcern Preventing Diaper Dropping & Sagging 76 71 That Would Cause YouConcern *Statistically significant over Comparative Example 1 with 90%confidence level

According to the consumer acceptance test results, Example 1 of thepresent invention, compared to Comparative Example 1, was acceptedbetter in all aspects of the product listed above, and was statisticallysignificantly better accepted in many aspects of the product. Inparticular, Example 1 was significantly conceived better in “OverallRating”, “Overall Softness”, and “Overall quality of the product”.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application, is hereby incorporated herein by reference in itsentirety unless expressly excluded or otherwise limited. The citation ofany document is not an admission that it is prior art with respect toany invention disclosed or claimed herein or that it alone, or in anycombination with any other reference or references, teaches, suggests ordiscloses any such invention. Further, to the extent that any meaning ordefinition of a term in this document conflicts with any meaning ordefinition of the same term in a document incorporated by reference, themeaning or definition assigned to that term in this document shallgovern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A wearable article comprising a main body and anelastic belt comprising a front belt and a back belt, the main bodybeing continuous with the front belt and the back belt, and thetransversely opposed side edges of the front belt and the back belt arejoined to form laterally opposed side seams such that a waist openingand two leg openings are formed; wherein each of the front belt and backbelt are formed by an inner sheet, an outer sheet, and a plurality ofelastic bodies sandwiched therebetween; wherein at least some of theelastic bodies run in the transverse direction substantially parallel toeach other; wherein each front belt and back belt have transverselycontinuous proximal and distal end edges, the proximal edge beinglocated closer than the distal edge relative to a transverse center axisof the article; wherein an entire length of the transverse edge of thefront belt is seamed with less than an entire length of the transverseedge of the back belt to define a seam length LS; wherein the front andback belts are each divided into 4 zones extending in the transversedirection and each zone being defined by its location from the distaledge to the proximal edge relative to the percentage of the seam lengthLS wherein; 0-25% is a waist zone, 25-50% is a distal tummy zone, 50-85%is a proximal tummy zone, and 85-100% is a leg zone; wherein the tensilestress of the front proximal tummy zone is higher than the tensilestress of any of the front waist zone, the front distal tummy zone, orthe front leg zone; and wherein the tensile stress of the back distaltummy zone is higher than any of the tensile stress of the back waistzone, the back proximal tummy zone, or the back leg zone.
 2. The articleof claim 1, wherein the tensile stress of the front proximal tummy zoneis higher than the tensile stress of any other zone.
 3. The article ofclaim 1, wherein the tensile stress of the front distal tummy zone islower than the tensile stress of the back distal tummy zone.
 4. Thearticle of claim 3, wherein the tensile stress of the front distal tummyzone is no more than 70% of the tensile stress of the back distal tummyzone.
 5. The article of claim 1, wherein the tensile stress of the frontleg zone is no more than 50% of the tensile stress of the front proximaltummy zone, and the tensile stress of the back leg zone is no more than100% of the tensile stress of the back proximal tummy zone.
 6. Thearticle of claim 1, wherein the tensile stress of the front leg zone isno more than 40% of the tensile stress of the front proximal tummy zone.7. The article of claim 1, wherein the tensile stress of the frontproximal tummy zone is no less than 200% of the tensile stress of thefront distal tummy zone.
 8. The article of claim 1, wherein the tensilestress of the front proximal tummy zone is no less than 150% of thetensile stress of the back proximal tummy zone.
 9. The article of claim1, wherein the tensile stress of the front leg zone is from 80% to 200%of the tensile stress of the back leg zone.
 10. The article of claim 1,wherein the tensile stress of the front waist zone is from 80% to 120%of the tensile stress of the back waist zone.
 11. The article of claim1, wherein the d value according to the Belt Seam Shape Measurementherein is no less than +10 mm.
 12. A wearable article comprising a mainbody and an elastic belt comprising a front belt and a back belt, themain body being continuous with the front belt and the back belt, andthe transversely opposed side edges of the front belt and the back beltare joined to form laterally opposed side seams such that a waistopening and two leg openings are formed; wherein each of the front beltand back belt are formed by an inner sheet, an outer sheet, and aplurality of elastic bodies sandwiched therebetween; wherein at leastsome of the elastic bodies run in the transverse direction substantiallyparallel to each other; wherein each front belt and back belt havetransversely continuous proximal and distal end edges, the proximal edgebeing located closer than the distal edge relative to a transversecenter axis of the article; wherein an entire length of the transverseedge of the front belt is seamed with less than an entire length of thetransverse edge of the back belt to define a seam length LS; wherein thefront and back belts are each divided into 4 zones extending in thetransverse direction and each zone being defined by its location fromthe distal edge to the proximal edge relative to the percentage of theseam length LS wherein; 0-25% is a waist zone, 25-50% is a distal tummyzone, 50-85% is a proximal tummy zone, and 85-100% is a leg zone; andwherein when comparing the 4 zones each of the front belt and the backbelt, the tensile stress is greatest in the order of: the front proximaltummy zone, followed by the back distal tummy zone.
 13. The article ofclaim 12, wherein the tensile stress of the front leg zone is no morethan 50% of the tensile stress of the front proximal tummy zone, and thetensile stress of the back leg zone is no more than 100% of the tensilestress of the back proximal tummy zone.
 14. The article of claim 12,wherein the tensile stress of the front leg zone is no more than 40% ofthe tensile stress of the front proximal tummy zone.
 15. The article ofclaim 12, wherein the tensile stress of the front proximal tummy zone isno less than 200% of the tensile stress of the front distal tummy zone.16. The article of claim 12, wherein the tensile stress of the frontdistal tummy zone is no more than 70% of the tensile stress of the backdistal tummy zone.
 17. The article of claim 12, wherein the tensilestress of the front proximal tummy zone is no less than 150% of thetensile stress of the back proximal tummy zone.
 18. The article of claim12, wherein the tensile stress of the front leg zone is from 80% to 200%of the tensile stress of the back leg zone.
 19. The article of claim 12,wherein the tensile stress of the front waist zone is from 80% to 120%of the tensile stress of the back waist zone.
 20. The article of claim12, wherein the d value according to the Belt Seam Shape Measurementherein is no less than +10 mm.